COMPARATIVE ANATOMICAL STUDIES ON THE DIFFERENT SYSTEMS OF COMMON INSECTIVORA FOUND IN EGYPT

Abstract

In the present investigation, the morphology, histology and histochemistry of the digestive system of two insectivorous mammals: the hedgehog, Hemiechirrus auritus and the shrew, Crocidura olivieri., have been investigated. The study has revealed the following:

The Digestive System

- The Tongue :

The tongue of the two animals is generally similar with respect to growth anatomy and general histology. It consists of mucosa, submucosa and muscularis. The mucosa of the hedgehog is keratinized whereas in the shrew it is nonkeratinized. The submucosa consists of an areolar connective tissue. The musculature of the tongue in is extremely complex. Inaddition, the tongue contains both mucous and serous glands.

The tongue has three types of papillae: the filiform which occupy the greater part of the tongue, the fungiform scattered between the filiform papillae, and circumvallate papillae. The later two types of papillae are similar in both animals. The circumvallate type are represented by three papillae located on the posterior third of the tongue.